Systems Operation

Usage:

Cooling Systems

Radiator Or Heat Exchanger

COOLING SYSTEM SCHEMATIC
1 - Aftercooler. 2 - Water temperature regulator housing. 3-Radiator. 4-Cylinder head. 5-Diesel engine cylinder block. 6-Diesel engine water pump. 7-Oil cooler.

Coolant is circulated by a gear driven, centrifugal-type water pump. Temperature regulators located at the front of the cylinder head, restrict coolant flow through the radiator or heat exchanger, until the coolant reaches operating temperature.

The water pump has two outlets. One outlet directs coolant to the aftercooler. The other outlet directs coolant to the engine oil cooler. Both streams join and are directed to the area around the cylinder liners, into the cylinder head, and then to the water temperature regulator housing.

Until the coolant reaches the temperature required to open the temperature regulators, coolant bypasses the radiator or heat exchanger and flows directly back to the water pump.

A pressure relief cap assembly is used to control the pressure in the cooling system. The cap allows pressure (and some water if the cooling system is too full) to escape when system pressure exceeds the relief pressure of the cap.

Raw Water Aftercooled With Expansion Tank And Heat Exchanger

Jacket water is circulated by a gear-driven, centrifugal-type water pump. Water temperature regulators located at the front of the engine, bypass coolant back to the water pump until the coolant reaches operating temperature.

Coolant from the diesel engine water pump is directed through a passage in the flywheel housing to the diesel engine oil cooler. From the diesel engine oil cooler, coolant is directed through the marine gear oil cooler into the cylinder block, around the cylinder liners, and into the cylinder head to cool the area around the precombustion chambers and cylinder head valves. Coolant is then directed to the water temperature regulator housing.

COOLING SYSTEM SCHEMATIC
1-Aftercooler. 2-Cylinder head. 3-Water temperature regulator housing. 4-Expansion tank. 5-Raw water pump. 6-Heat exchanger. 7-Diesel engine oil cooler. 8-Marine gear oil cooler. 9-Diesel engine water pump. 10-Turbocharger heat shield. 11 - Exhaust manifold heat shield. 12 - Diesel engine cylinder block.

Coolant is also directed to the turbocharger and exhaust manifold heat shields. The coolant then flows to the water temperature regulator housing where it joins with coolant from the cylinder head. Until the coolant reaches normal operating temperature, it is bypassed back to the water pump.

Raw water is circulated by a gear-driven, centrifugal-type water pump. Coolant is directed to the aftercooler, to the heat exchanger and then to waste.

Keel Cooled (Marine)

Coolant is circulated by a gear-driven centrifugal type water pump. Temperature regulators located at the front of the engine, bypass coolant flow back to the water pump until the coolant reaches normal operating temperature.

Coolant flow is divided at the water pump. A portion of the coolant is directed to the aftercooler, and then flows into the cylinder block. The remainder of the coolant flows through the engine oil cooler to the marine gear oil cooler, and then enters the cylinder block. Coolant from the pump is also directed to the turbocharger water shield, exhaust manifold water shield, and then to the temperature regulator. Coolant in the cylinder block is directed around the cylinder liners, into the cylinder head, around the pre-combustion chambers and then to the temperature regulator housing.

COOLING SYSTEM SCHEMATIC
1-Aftercooler. 2-Cylinder head. 3-Water temperature regulator housing. 4-Expansion tank. 5-Cylinder block. 6-Diesel engine oil cooler. 7-Marine gear oil cooler. 8-Diesel engine water pump. 9-Turbocharger and exhaust manifold water shields. 10-Keel cooler.

When the coolant reaches normal operating temperature, the temperature regulators direct the coolant to the keel cooler and then to the expansion tank.

Lubrication System

LUBRICATION SYSTEM COMPONENTS
1-Camshaft journal oil supply line. 2-Turbocharger oil supply line. 3-Oil filter. 4-Oil manifold in cylinder block. 5-Turbocharger oil drain line. 6-Oil pump (located within oil pan). 7-Oil pan (sump). 8-Oil cooler.

The lubrication system consists of a sump (oil pan), oil pump, oil cooler and oil filter. The engine contains an oil manifold and oil passages to direct lubricant to the various components.

The oil pump draws lubricant from the sump and forces it through the oil cooler, oil filter, and then into the oil manifold. Oil flows through connecting passages to lubricate the engine components. A regulating valve in the pump body controls the maximum pressure of the oil from the pump.

When the engine is started, the lubricating oil in the oil pan is cold (cool). This cool oil forces bypass valves in the oil filter base to open, and allows an immediate oil flow through the engine. When pressure through the oil cooler and oil filter has been equalized, the turbocharger lubrication valve closes. Filtered oil is then delivered to the turbocharger.

As oil viscosity and pressure decrease the oil filter bypass valve closes. Oil temperature continues to increase and the oil cooler bypass valve closes. Oil now flows through the oil cooler and oil filter before reaching the engine components.

A contaminated or restricted oil filter element will not prevent lubricating oil from being delivered to the engine components. The oil filter bypass valve will open, allowing oil to bypass the element.

An oil manifold, cast into the cylinder block, directs lubricant to the main bearing supply passages. Oil is also directed up through the cylinder head to lubricate the camshaft journals and the camshaft idler (drive) gears.

Oil spray orifices in the cylinder block spray oil on the underside of the pistons. This cools the pistons and provides lubrication for the piston pins, cylinder walls and piston rings.

The connecting rod bearings receive oil through drilled passages in the crankshaft between the main bearing journals and connecting rod journals.

When the engine is warm and running at rated speed, the oil pressure gauge should register in the "operating range". A lower pressure reading is normal at idling speeds.

Fuel System

The fuel system is a pressure type with a separate injection pump and injection valve for each cylinder. Fuel is injected into a precombustion chamber, not directly into the cylinder.

FUEL SYSTEM COMPONENTS
1-Fuel filter base and final fuel filter. 2-Vent valve. 3-Fuel priming pump. 4-Fuel injection valves (six, located in cylinder head, under valve cover). 5-Fuel transfer pump. 6-Fuel injection pump housing.

A transfer pump supplies fuel to a manifold in the injection pump housing. Fuel is directed through a fuel filter before it enters the manifold.

The transfer pump can supply more fuel than is required for injection, so a bypass valve is built into the system. The valve limits the maximum pressure to the injection pumps.

The injection pumps receive fuel from the manifold and force it under high pressure to the injection valves. The injection valves spray atomized fuel into the precombustion chambers.

An air vent valve in the system permits removal of air. Air is removed by opening the valve and pressurizing the fuel system. The system can be pressurized by using the priming pump. The vent valve must be open until a stream of fuel, without air bubbles, flows from the vent line.

Fuel Injection Pump Operation

The injection pump plungers and the lifters are lifted by lobes on the camshaft and always make a full stroke. The lifters are held against the cam lobes by springs.

The amount of fuel pumped each stroke is varied by turning the plunger in the barrel. Action of the governor moves the fuel rack which turns the pump gear segment on the bottom of the pump plunger.

FUEL INJECTION PUMP HOUSING
1-Fuel manifold. 2-Inlet port. 3-Check valve. 4-Gear segment. 5-Pump plunger. 6-Spring. 7-Fuel rack. 8-Lifter. 9-Camshaft.

Governor Operation

When the engine is operating, the balance between the centrifugal force of revolving weights (12) and the force of spring (5) controls the movement of valve (13). The valve directs pressure oil to either side of rack-positioning piston (14). Depending on the position of the valve (13), piston (14) will move the rack to increase or decrease fuel to the engine to compensate for load variation.

Pressurized lubrication oil, directed through passages in the fuel injection pump housing, enters passage (16) in the governor cylinder. The oil encircles sleeve (15) within the cylinder. Oil is then directed through a passage in piston (14) where it contacts valve (13).

When engine load increases, engine RPM decreases and revolving weights (12) slow down. The weights move toward each other and allow governor spring (5) to move valve (13) forward. As valve (13) moves, an oil passage around valve (13) opens to pressure oil. Oil then flows through passage (7) and fills the chamber behind piston (14). The pressure forces the piston and rack forward, increasing the amount of fuel to the engine. Engine RPM increases until the revolving weights rotate fast enough to balance the force of the governor spring.

HYDRAULIC GOVERNOR (Typical Example)
1-Collar. 2-Speed limiter plunger. 3-Lever assembly. 4-Seat. 5-Governor spring. 6-Thrust bearing. 7-Oil passage. 8-Drive gear (weight assembly). 9-Cylinder. 10-Bolt. 11-Spring seat. 12-Weight. 13-Valve. 14-Piston. 15-Sleeve. 16-Oil passage. 17-Fuel rack. The governor valve is shown in the position when the force of the weights and the force of the spring are balanced.

When engine load decreases, engine RPM increases, revolving weights (12) speed-up, and the toes on the weights move valve (13) rearward, allowing the oil behind piston (14) to flow through a drain passage opened at the rear of the piston. At the same time, the pressure oil between sleeve (15) and piston (14) forces the piston and rack rearward, decreasing the amount of fuel to the engine. Engine RPM decreases until the revolving weights balance the force of the governor spring.

When the engine is started, speed limiter plunger (2) restricts the movement of the governor control linkage. When operating oil pressure is reached, the plunger in the speed limiter retracts and the governor control can be moved to the HIGH IDLE position.

When engine RPM is at LOW IDLE, a spring-loaded plunger within lever assembly (3) in the governor bears against the shoulder of the low idle adjusting screw. To stop the engine, the control linkage must force the plunger past the shoulder on the adjusting screw.

Oil from the engine lubricating system lubricates the governor weight bearing. The various other parts are splash lubricated. Oil from the governor drains into the fuel injection pump housing.

Fuel Injection Valve

Fuel, under high pressure from the injection pumps, is transferred through the injection lines to the injection valves. As high pressure fuel enters the nozzle assembly, the check valve within the nozzle opens and permits the fuel to enter the precombustion chamber. The injection valve provides the proper spray pattern.

FUEL INJECTION VALVE CROSS SECTION
1-Fuel line assembly. 2-Nut. 3-Glow plug. 4-Nozzle assembly. 5-Precombustion chamber.

Electrical System

The electrical system is a combination of two separate electric circuits: the charging circuit and starting circuit. Each circuit is dependent on some of the same components. The battery (batteries), disconnect switch, circuit breaker, ammeter, cables and wires from the battery are, usually, common in each of the circuits.

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NOTICE

The disconnect switch must be ON to allow the electrical system to function. Some charging circuit components will be damaged if the engine is operated with the disconnect switch OFF.

The charging circuit is in operation when the diesel engine is operating. The electricity producing (charging) unit is an alternator or a generator. A regulator in the circuit senses the state of charge in the battery and regulates the electrical output to keep the battery fully charged.

The starting circuit operates only when the disconnect switch is ON and the start switch is actuated.

The direct electric diesel engine starting circuit may include a glow plug for each diesel engine cylinder. Glow plugs are small heating elements in the precombustion chambers which promote fuel ignition when the engine is started in low temperatures.

The load and charging circuits are both connected on the same side of the ammeter while the starting circuit connects to the other side of the ammeter.

System Components

Alternator-5L1243

ALTERNATOR COMPONENTS
1-Brushes. 2-Stator. 3-Fan. 4-Slip rings. 5-Collar. 6 and 7-Bearings. 8-Rotor.

This alternator is a three phase self-rectifying charging unit.

The alternator has four main components: end frame assembly (brush end), rotor assembly, stator and shell assembly, and end frame assembly (drive end).

Alternator Regulator

The regulator senses the charge condition of the battery as well as electrical system power demand and controls the alternator output accordingly by limiting the field current.

ALTERNATOR REGULATOR
1-Plug. 2-Connector.

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NOTICE

Never operate the alternator without the battery in the circuit. Making or breaking an alternator connection with a heavy load on the circuit will sometimes result in regulator damage.

Alternator-5S9088

ALTERNATOR

This alternator is a belt driven, three phase, self-rectifying, brushless unit with a built-in voltage regulator.

The only movable part in the assembly is the rotor, which is mounted on a ball bearing at the drive end, and a roller bearing at the rectifier end.

The regulator is enclosed in a sealed compartment. It senses the charge condition of the battery and the electrical system power demands and controls the alternator output accordingly.

Generator

The generator (is driven by the diesel engine) keeps the battery charged, and supplies current to operate the electrical components.

CUTAWAY VIEW OF A GENERATOR

Generator Regulator

The generator regulator controls the output of the generator. The regulator incorporates three controls: the cutout relay, the voltage regulator and the current regulator. Each control has contact points which are operated by electromagnets.

GENERATOR REGULATOR

Springs hold the cutout relay points open and the voltage regulator and current regulator contact points closed. The spring tension for each unit is a force opposing the force of the electromagnets.

The cutout relay prevents the battery from motorizing a generator that is not producing enough voltage. Generator voltage approximately equal to battery voltage will close the cutout relay points. This closes the circuit between the generator and the battery. The generator can now supply the battery and the components of the electrical system with power.

The voltage regulator prevents the generator from producing damaging high voltage. Generator voltage slightly higher than battery voltage opens the regulator points causing the generator output voltage to lower. Low generator voltage allows the spring to close the regulator points and generator voltage is again high. The action of the voltage regulator points, opening and closing, controls the output voltage of the generator. The points can open and close as often as 200 times per second.

The current regulator limits the current produced by the generator to allow the generator to continue producing voltage equal to battery voltage. When the generator produces current equal to the current regulator setting, the regulator contact points open. Open points lower the generator current. Low current allows the spring to close the points and generator current is again high. The opening and closing of the current regulator points, limits the current produced by the generator. The points can open and close as often as 200 times per second.

When generator electric loads are low and the battery requires very little charging, the VOLTAGE REGULATOR contact points are operating. When electric loads are high, the CURRENT REGULATOR contact points are operating. The contact points, of the two units, will never open at the same time.

This is a schematic wiring diagram of the generator regulator in a battery charging system.

Starting Motor

The starting motor used with direct electric start incorporates a solenoid. The action of the solenoid engages the pinion with the ring gear on the engine flywheel, when the solenoid is energized. The pinion always engages before the electric contacts in the solenoid close the circuit between the battery and the starting motor. An overrunning clutch protects the starting motor from being overspeeded. Releasing the start-switch disengages the pinion from the ring gear on the flywheel.

24V STARTING MOTOR

SCHEMATIC OF A SOLENOID

A solenoid is a magnetic switch that utilizes low current to close a high current circuit. The solenoid has an electromagnet with a movable core. There are contacts on the end of the core. The contacts are held open by a spring that pushes the core away from the magnetic center of the coil. Low current will energize the coil and form a magnetic field. The magnetic field draws the core to the center of the coil and the contacts close.

Diagrams

A variety of electrical systems can be used with these engines. Some systems are available with one 32 volt, 24 volt or 12 volt starting motor. Other systems without electric starting motors are provided for use with air starting and hydraulic starting.

Glow plugs provide for low temperature starting. Glow plugs are not required where ideal starting conditions exist. These diagrams show only the HEAT-START switch with glow plugs. Systems without glow plugs use a push button switch with two post connections to energize the starter solenoid.

A fuel pressure switch in a system prevents alternator field excitation. Thus damage to the alternator from the battery is prevented when the engine is not operating.

Automatic START-STOP wiring diagrams are shown for the complete system in the ATTACHMENT section of this manual.

Negative Ground Systems

These systems are most often used in applications where no special precautions are necessary to prevent local radio interference and/or electrolysis of grounded components.

NEGATIVE GROUND 32V-60 AMP. SYSTEM WITH GLOW PLUGS (DELCO REMY)

NEGATIVE GROUND 24V-18 AMP., 12V-24 AMP. OR 32V-18 AMP. SYSTEM WITH GLOW PLUGS FOR USE WITH AIR OR HYDRAULIC STARTING (DELCO-REMY)

NEGATIVE GROUND 24V-18 AMP., 12V-24 AMP. OR 32V-18 AMP. SYSTEM WITH GLOW PLUGS (DELCO REMY)

NEGATIVE GROUND 32V-60 AMP. SYSTEM WITH GLOW PLUGS FOR USE WITH AIR OR HYDRAULIC STARTING (DELCO REMY)

Insulated Systems

These systems are most often used in applications where radio interference is undesirable or where conditions are such that grounded components would corrode from electrolysis.

INSULATED 32V-60 AMP. SYSTEM WITH GLOW PLUGS (DELCO REMY)

INSULATED 24V-18 AMP., 12V-24 AMP. OR 32V-18 AMP. SYSTEM WITH GLOW PLUGS FOR USE WITH AIR OR HYDRAULIC STARTING (DELCO REMY)

INSULATED 32V-60 AMP. SYSTEM WITH GLOW PLUGS FOR USE WITH AIR OR HYDRAULIC STARTING (DELCO REMY)

INSULATED 24V-18 AMP., 32V-18 AMP. OR 12V-24 AMP. SYSTEM WITH GLOW PLUGS (DELCO REMY)

Problem Solving

1. Engine Fails to Start

2. Misfiring

3. Stalls at Low Speed

4. Erratic Engine Speed

5. Low Power

6. Excessive Vibration

7. Heavy Combustion Knock

8. Valve Train Clicking Noise

9. Oil in Coolant

10. Mechanical Knock

11. Excessive Fuel Consumption

12. Loud Valve Train Noise

13. Excessive Valve Lash

14. Valve Rotator or Spring Retainer Free

15. Slobber

16. Valve Lash Close-up

17. Premature Engine Wear

18. Coolant in Engine Lubricating Oil

19. Excessive Black or Gray Smoke

20. Excessive White or Blue Smoke

21. Low Engine Oil Pressure

22. High Lubricating Oil Consumption

23. Abnormal Engine Coolant Temperature

24. Starting Motor Fails to Crank

25. Alternator Fails to Charge

26. Alternator Charging Rate Low or Unsteady

27. Alternator Charging Rate Excessive

28. Noisy Alternator

Cooling System

The engine has a pressurized cooling system. Pressurizing the cooling system serves two purposes. First, it permits safe operation at coolant temperature higher than the normal boiling point; thereby, providing a margin of cooling for those intermittent peak loads. Secondly, it prevents cavitation in the water pump and reduces the possibility of air or steam pockets forming in the coolant passages.

Many times, overheating of the engine is caused by failure to make simple systematic inspections. Visual inspections should be made before instrumentation testing.

Visual Inspection

1. Check coolant level.

2. Inspect for leaks in the system.

3. Inspect the radiator fins. Be certain the air flow through the radiator is not restricted by trash or bent radiator fins.

4. Check fan belts.

5. Check for damaged fan blades.

6. Observe if there is any air or combustion gas in the cooling system.

7. Check to see that the expansion tank, heat exchanger or radiator cap sealing surfaces are clean.

8. Check for lack of raw water inlet and outlet flow.

Testing Cooling System

Remember that temperature and pressure go hand-in-hand and neither one can be tested logically without considering the other. For example, the effect of pressurization and altitude on the boiling point of water is shown in the chart.

Temperature Gauge

2F7112 Thermometer, 6B5072 Bushing.

If overheating and loss of coolant is a problem, a pressure loss in the system could be the cause. If an overheating condition is indicated on the temperature gauge and loss of coolant is not evident, check the accuracy of the temperature gauge. Make this check by installing a 2F7112 Thermometer (using a 6B5072 Bushing) into the cylinder head.

THERMOMETER INSTALLED

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NOTICE

when working around an engine if it is running.

Start the engine. Partially cover the radiator or reduce flow of raw water to reduce cooling. The instrument panel temperature gauge should enter ranges at points 1, 2, 3 and 4 when the test thermometer indicates temperatures shown in the chart.

Pressure Cap

If the pressure check indicates that the system is unable to hold pressure, the source of the pressure leak must be determined. One of the causes of cooling system pressure loss can be a faulty pressure cap seal. Inspect the pressure cap carefully for possible damage to the seal or sealing surfaces. The build-up of deposits on the cap, seal and filler neck should be removed.

Water Temperature Regulator

The opening temperature of the regulator (bench test in atmospheric pressure) is approximately 165° ± 1°F (74° ± 1°C). The regulator should be fully open at approximately 185°F (85°C).

Air Induction And Exhaust Systems

Restriction Of Air Inlet And Exhaust

Engine horsepower and efficiency will be reduced if either the air inlet or exhaust system becomes restricted.

The air cleaner should not restrict air flow more than 30" (762 mm) of water difference in pressure.

Exhaust back pressure (pressure difference measured between the turbocharger outlet elbow tap and the ambient air) should be no more than 15" (381 mm) of water, difference in pressure.

Measuring Inlet Manifold Pressure

By checking inlet manifold pressure, and comparing that pressure with the RACK SETTING INFORMATION, one can determine if an engine is operating efficiently. This test should be used if engine horsepower seems to be too low, yet no specific symptom of engine trouble is apparent.

Inlet manifold pressures in the RACK SETTING INFORMATION are recorded under specific operating conditions: 29.4 inches (746,76 mm) of mercury barometric pressure, 85° F. (29.4° C.) ambient temperature and 35 API rated fuel. Any deviation from these conditions can affect the inlet manifold pressure. Ambient air which is denser than that at 85°F./29.4 inches (29.4°C./746,76 mm) of mercury, can cause a slightly higher horsepower and inlet manifold pressure reading than listed in the RACK SETTING INFORMATION. If the ambient air is less dense, the horsepower and inlet manifold pressure rating can be slightly lower. Fuel density (API gravity rating) also affects the horsepower and inlet manifold pressure. If the fuel is rated above the standard 35 API gravity rating, the inlet manifold pressure can be slightly less than the value given in the RACK SETTING INFORMATION. If the fuel is rated below the standard rating, the inlet manifold pressure can be slightly more. BE SURE THE AIR INLET AND EXHAUST ARE NOT RESTRICTED WHEN CHECKING INLET MANIFOLD PRESSURE.

INLET MANIFOLD PRESSURE TEST LOCATION
1-Plug (viewed from top of engine).

The components in a 4S6553 Instrument Group provide a means of reading engine RPM and inlet manifold pressure simultaneously. This group contains an instantaneous reading tachometer and a gauge for reading inlet manifold pressure. Instructions (FE036044) included with this group, explain the testing procedure.

Crankcase Pressure

Excessive crankcase pressure can be a result of combustion gas leaking past broken or damaged pistons and/or piston rings. This condition will usually be accompanied by irregular engine operation and excess fumes from crankcase breather opening. This pressure can cause the breather element to become restricted in an unusually short time. In addition, it can cause engine oil to leak past gaskets and seals that would function properly under normal conditions.

Camshaft Installation

1. Extreme caution should be exercised to be sure that all the camshaft followers are adjusted to provide maximum clearance before installation of the camshafts.

2. Rotate the crankshaft until No. 1 cylinder is at top center on the compression stroke.

3. Position the camshaft phasing gear timing marks (1) together and in a horizontal plane as shown.

CAMSHAFT PHASING GEARS
1-Timing marks.

4. Install the camshaft assembly.

5. Install the cam driveshaft with the blind spline on top.

6. Install the glow plug lead assembly and connect the leads to the glow plugs.

7. Adjust the valve clearance.

Fuel System

Difficulty within the fuel system can be classed in one of two groups: lack of fuel or too much fuel for proper combustion.

Many times, the fuel system is blamed when the fault lies elsewhere, especially when smoky exhaust is the problem. Smoky exhaust can be the result of a faulty fuel injection valve, but it can also be caused by lack of air for complete combustion, overloading at high altitude, excessive oil burning or lack of compression.

Visual Inspection

1. Observe the fuel pressure gauge reading. Lack of pressure indicates difficulty in the supply side of the system.

2. Check the fuel level in the supply tank and the fuel tank cap vent for being plugged.

3. See that the vent valve is closed.

4. Check for leakage in the fuel supply lines and components or for a kinked or restricted supply line.

5. Replace the fuel filter element and clean the primary fuel filter.

6. Inspect the fuel bypass valve to see that it moves freely and that dirt is not holding the plunger off its seat. Be certain the spring has proper tension.

7. Bleed the fuel system to remove trapped air.

Fuel Injection Service

When installing a fuel injection valve, always check the seats of both the nozzle and the precombustion chamber. The nozzle assembly should be only finger-tight on the body. It is important to maintain the nozzle retaining nut torque to 105 ± 5 lb. ft. (14,5 ± 0,7 mkg). EXCESSIVE TORQUE will damage the nozzle. LESS TORQUE will allow the nozzle to leak and may cause the nozzle case to bulge or split.

RACK CENTERING PIN LOCATION
1-Cover.

The fuel rack must be held at the center or "zero" position while removing or installing a fuel injection pump. An injection pump installed in the "fuel on" side of its gear segment can cause the engine to overspeed with resultant serious damage to the engine and driven equipment.

The rack is positioned at the center or "zero" position by using a centering pin, located under cover (1). To center the rack, move the rack to the shutoff position, loosen cover (1) and depress the centering pin.

NOTE: Hold pin down in the centered position by placing cover (1) partially over the centering pin, and tightening bolt finger tight.

Depress the speed limiter plunger, and move the governor control lever toward the fuel on position until the rack contacts the centering pin. The rack is now centered.

When removing fuel injection pumps, spacers and lifters, the components should be kept together and marked so they can be installed in their respective location.

While disassembling fuel injection pumps, exercise considerable care to prevent damage to the plunger surfaces. The barrel and the plunger assembly are matched and the individual parts are not interchangeable with other barrels or plunger assemblies. Use extreme care when inserting the plunger into the bore of the barrel.

When a fuel injection pump is installed properly, the retaining bushing can be screwed-in finger-tight, flush with the top of the fuel injection pump housing. If the bushing cannot be turned flush with the top of the housing, the notch in the bonnet is not aligned with the dowel in the housing, or the slot in the gear segment is not aligned with the dowel in the lifter. It is important to maintain the final tightening torque of the retaining bushing to 150 ± 10 lb. ft. (20,7 ± 1,4 mkg).

Testing Fuel Injection Equipment

Before attempting to test a fuel injection pump or valve from an engine that is missing or puffing black smoke, a simple check can be made to determine which cylinder is causing the difficulty. With the engine running at a speed which makes the defect most pronounced, momentarily loosen the fuel line nut on the injection pump sufficiently to "cut out" the cylinder. Check each cylinder in the same manner. If one is found where loosening makes no difference in the irregular operation or causes puffing or black smoke to cease, the pump and valve for only that cylinder need be tested.

Checking Fuel Injection Valve

1. Excessive carbon on tip of nozzle or in orifice.

2. Erosion of the orifice.

3. Screen plugged with dirt.

The condition of a capsule-type nozzle assembly can be tested on the Caterpillar Diesel Fuel Injection Test Apparatus, and the rate of leakage of the nozzle assembly can be determined.

Checking Fuel Injection Pump Lifter Washer and Pump Plunger

The timing dimension should be checked and adjusted, if necessary, with the fuel injection pump off the engine. If the timing dimension is too small, injection will begin early, and if too great, injection will be late.

When pump plunger wear becomes excessive, the lifter washer may also be worn so it will not make full contact with the end of a new plunger. To avoid rapid wear on the end of the new plunger, replace the lifters having washers showing visible wear.

These are patterns of wear between washer and plunger. Fig. A illustrates the contact surfaces of a new pump plunger and a new lifter washer. In Fig. B the pump plunger and lifter washer have worn considerably. Fig. C shows how the flat end of a new plunger makes poor contact with a worn lifter washer resulting in rapid wear to both parts.

A pump can maintain a satisfactory discharge rate and yet be unserviceable because of delayed timing resulting from wear on the lower end of the plunger. When testing a pump which has been in use for a long time, check the plunger length with a micrometer. Discard the pump if the plunger measures less than the minimum length (worn) dimension.

Inspect the upper diameter of the plunger for wear. The performance of pumps worn in this manner can be checked as described in the Instructions for Fuel Injection Test Apparatus.

Fuel System Adjustments

8S7167 Gauge.6F6922 Depth Micrometer with a 4 to 5 in. (101,6 to 127,0 mm) rod.1F8747 Plate Assembly.8S2346 Shaft in place of 7F8751 Shaft.8S2348 Pointer Assembly.

Locating Top Dead Center Compression Position For No. 1 Piston

No. 1 piston on the compression stroke at top center (TC) is the reference point for all timing procedures.

Remove the valve cover. The four valves at the front of the engine are the inlet and exhaust valves for No. 1 cylinder.

TIMING POINTER COVER LOCATION
1-Timing pointer cover.

With a pry bar, rotate the flywheel clockwise (as viewed from the flywheel end of the engine) at least 30° past the timing mark.

1. Now rotate the flywheel counterclockwise (as viewed from the flywheel end of the engine) until one of the following timing marks aligns with the timing pointer:

a. Industrial engine timing mark is TC1-6.

b. Marine engine timing mark is "3".

NOTE: If timing mark passes timing pointer, do not back up, repeat Step 1 again.

Fuel Injection Pump Camshaft Timing

The fuel pump camshaft timing can be checked and reset, if necessary, in the following manner:

1. Locate (TDC) compression position for No. 1 piston. Refer to the topic LOCATING TOP DEAD CENTER COMPRESSION POSITION FOR NO. 1 PISTON.

2. Remove timing pin (2) and cover (1). Install timing pin (1) back into the hole it was taken out of, until the end of the pin engages the timing slot in the fuel injection pump camshaft. Timing pin must be free in timing slot of camshaft.

TIMING PIN LOCATION
1-Timing hole cover. 2-Timing pin.

3. If the timing pin will not engage the slot in the fuel injection pump camshaft, proceed as follows:

COUPLING BOLT LOCATION
3-Bolts (two).

4. Remove the cover over the accessory drive housing. Loosen coupling bolts (3) retaining the accessory drive gear to the variable timing drive shaft. Retighten the coupling front bolt to 10 lb. ft. (1,4 mkg).

5. Rotate the camshaft until timing pin (2) engages the timing slot in the fuel injection pump camshaft. Timing pin (2) must be free in the camshaft slot.

6. Remove timing pin (2) and tighten bolts (3) and lock.

7. Rotate flywheel counterclockwise two complete turns (as viewed from the flywheel end) until flywheel timing mark aligns with timing pointer.

NOTE: If flywheel timing mark is passed, do not back up, repeat Step 7.

8. Fuel injection pump camshaft timing pin should freely engage the timing slot in the fuel injection pump camshaft. If the timing pin does not engage the slot in the fuel injection pump camshaft, repeat the complete timing procedure.

Checking Fuel Injection Pump Timing-On Engine

Checking With 3S2954 Timing Indicator Group

MEASURING PISTON TRAVEL
1-3S3263 Adapter. 2-9M9268 or 9S215 Dial indicator. 3-3S3264 Rod. 4-Precombustion chamber. 5-Inlet port. 6-Piston. 7-Crankshaft.

Travel of piston (6), from point of closing inlet port (5) to top center, can be found by using 3S2954 Timing Indicator Group. Convert the travel of piston (6) into degrees to determine if the timing is correct.

1. Install the timing indicator group as outlined in instructions included with the group.

2. Disconnect fuel line from corresponding fuel injection pump and move governor control to full load position.

3. Maintain 10 to 15 PSI fuel pressure with filter housing hand pump, or apply air pressure of 10 to 15 PSI to fuel tank.

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NOTICE

Air pressure in fuel tank exceeding 15 PSI can damage tank. If shop air is used, a 4L4454 Valve, or its equivalent, must be used to regulate air pressure to less than 15 PSI. Engine fuel shutoff valve, if so equipped, must be in open position.

4. Rotate crankshaft (7) very slowly in normal direction until fuel flow is reduced to approximately 6 drops per minute [point of closing inlet port (5)] from injection pump. Zero dial indicator (2) in cylinder.

5. Release the air pressure in system.

6. Continue to rotate crankshaft until dial indicator (2) reads maximum value (piston at top center).

7. Consult chart to find angle corresponding to maximum indicator reading. Angle should be fuel pump timing specified.

Fuel Pump Timing Dimension Setting-Off Engine

Use only the OFF ENGINE method to check and adjust a fuel pump timing dimension setting.

Typical example of checking timing dimension setting with: 1-Spacer. 2-8S7167 Gauge. 3-6F6922 Depth Micrometer, 4 to 5 in. (101,6 to 127,0 mm) rod. The timing dimension is indicated by "A".

Proceed with off engine timing using an 8S7167 Gauge, 6F6922 Depth Micrometer, 4 to 5 in. (101,6 to 127,0 mm) rod, 1F8747 Plate Assembly (with 8S2346 Shaft in place of the standard 7F8751 Shaft and an 8S2348 Pointer Assembly.

1. Install the 8S2348 Pointer Assembly on the fuel injection pump housing.

2. Install the 8S2346 Shaft on the drive end of the fuel injection pump camshaft.

3. Place a 9S9114 Spacer on the 8S2346 Shaft, and then install the 1F8747 Plate Assembly. Secure the plate to the shaft.

4. Refer to the chart and select the timing plate degree setting for the lifter being checked or set. Set the timing plate by rotating it clockwise until the proper degree setting aligns with the pointer assembly. Lock in position with the lockscrew.

5. The fuel injection pump timing dimension (off engine), using the 8S7167 Gauge is 4.390-4.394 in. (111,506-111,607 mm).

6. The spacer must be changed to change the timing dimension.

7. If all timing dimensions are to be checked or reset, continue the same procedure in the firing order of the engine. Recheck each timing dimension after the adjustment has been made, to make sure the dimension is correct.

NOTE: At installation, the fuel injection pump camshaft must be timed to the engine crankshaft. See the topic FUEL INJECTION PUMP CAMSHAFT TIMING.

Fuel Rack Setting-Using The 9S240 Rack Positioning Tool Group, 9S215 Dial Indicator And 8S4627 Circuit Continuity Tester

The 9S240 Rack Positioning Tool Group makes it possible to set the rack, or measure rack position, during normal operation of the engine. The ability to observe rack position during operation, can provide much of the needed data to determine actual horsepower output and diagnose the cause for lack of power.

PREPARING TO ADJUST FUEL RACK
1-Cover. 2-Plug.

1. Refer to the RACK SETTING INFORMATION to obtain the correct rack setting dimension.

2. Disconnect the governor control linkage, at the most convenient location, so the governor control lever moves freely throughout its entire length of travel.

TOOLS INSTALLED
3-9S215 Dial Indicator with 9S8883 Contact Point. 4-Cover. 5-Rack centering pin. 6-9S7343 Bracket.

3. Remove the fuel ratio control from the rear of the governor (if so equipped).

4. Install rack positioning tool group and 9S215 dial indicator. Dial indicator contact point to go through opening for plug (2).

5. Move governor control lever to shutoff position. Loosen cover (4) and depress rack centering pin (5) so it engages the slot in the rack.

NOTE: Hold pin down in centered position, by placing cover (4) partially over the centering pin, and tightening the retaining bolt finger tight.

6. Depress the speed limiter plunger with 9S8521 Rod and 9S8518 Plug, and move the governor control lever toward the fuel-on position until the slot in the rack contacts the rack centering pin. The rack is now centered. Zero the dial indicator and remove rack centering pin.

7. Attach one end of the 8S4627 Circuit Continuity Tester to the brass screw terminal on the cylinder block side of the governor housing. Ground the other end.

8. Rotate the governor control lever toward the fuel-on direction until the tester light comes on bright.

9. Slowly, rotate the governor control lever toward the shutoff position until the light goes out.

10. Now, again slowly rotate the governor control lever toward the fuel-on position, until the tester light just barely comes on (a dim light); rack collar is now just touching the stop bar. Rack setting can now be read directly from the 9S215 Dial Indicator.

11. If rack needs adjustment remove the governor housing rear cover, and refer to topic RACK ADJUSTMENT.

Rack Adjustment

ADJUSTING FUEL RACK
1-Screw. 2-Lock nut. 3-4B9820 Wrench.

Move governor control lever to the shutoff position.

NOTE: Loosen locknut (1) and turn adjusting screw (2) with wrench (3) to adjust rack travel. Never adjust rack travel with shims.

Check adjustment by performing Steps 5 through 10 in the topic FUEL RACK SETTING - USING THE 9S240 RACK POSITIONING TOOL GROUP, 9S215 DIAL INDICATOR AND 8S4627 CIRCUIT CONTINUITY TESTER. Continue adjustment procedure until the reading on the dial indicator is the same as the setting given in the RACK SETTING INFORMATION.

After the rack has been adjusted, tighten lock nut (1) to 11 plusmn;1 lb. ft. (1,5±0,14 mkg).

Governor Adjustments

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NOTICE

Only competent personnel should attempt to adjust the low and high idle RPM. The low and high idle RPM, and the rack setting dimensions for this engine, are listed in the RACK SETTING INFORMATION.

Engine RPM should be checked with an accurate tachometer.

GOVERNOR ADJUSTMENTS
1-Low idle adjusting screw. 2-High idle adjusting screw. 3-Cover. 4-Retainer holes (two).

Low and high idle RPM can be adjusted by removing the cover at the rear of the governor, and turning the high idle and low idle adjusting screws. Turning either adjusting screw in a clockwise direction will decrease the respective high and low idle RPM. The retainer holes in the cover are shaped to prevent the screws from turning, after the adjustment has been made.

After setting the idle RPM, move the governor control lever to change the engine RPM. Return it to the idle position and recheck the idle RPM. Repeat the adjustment procedure until the specified idle RPM is obtained.

Fuel Ratio Control Setting (Engines so equipped)

9S240 Rack Positioning Tool Group.

The fuel rack must be set correctly before setting the fuel ratio control.

1. Remove the rack cover plug from the accessory drive housing, and cover (2) from the rear of the fuel ratio control.

2. Engage slot in cover (2) with cross-dowel in adjusting bolt and turn the adjusting bolt in as far as possible. This prevents the head of the bolt from limiting the travel of the fuel rack.

3. Install 9S7343 Bracket over the front end of the fuel rack and 9S215 Dial Indicator in the bracket.

SETTING FUEL RATIO CONTROL (Typical Example)
1-Governor control lever. 2-Cover. 3-9S8518 Plug. 4-9S8521 Rod.

4. Remove the speed limiter access plug from the bottom of the governor and install plug (3). Through opening in plug (3) use rod (4) to push in (retract) the speed limiter plunger. Tighten plug (3) just enough to impose a clamping action on rod (4).

5. Center the rack and "zero" the dial indicator.

6. Move governor control lever (1) to FULL LOAD position. Hold the lever in the FULL LOAD position while making the adjustment.

7. Turn adjusting bolt out with cover (2) until the correct reading on the dial indicator is obtained. The correct reading is listed in the RACK SETTING INFORMATION.

8. Turn cover (2) clockwise the amount necessary to align bolt holes and install cover (2).

9. Remove the 9S7343 Bracket, 9S215 Dial Indicator and install the rack cover plug.

10. Remove plug (3) and install the standard plug.

NOTE: Before starting the engine, make certain the governor control lever will move the governor to the SHUTOFF position and that all parts operate freely.

With the above initial adjustment made, a further adjustment can be made while the engine is running (if necessary) to improve engine performance. To reduce exhaust smoke during acceleration, turn cover (2) out (less fuel) 1/2 turn at a time until satisfactory. When exhaust smoke is acceptable but acceleration is sluggish, turn cover (2) in (more fuel) 1/2 turn at a time until satisfactory.

NOTE: Some exhaust smoke is likely to appear at maximum acceleration.

If acceleration is sluggish and full engine power seems to be lost, inspect the air line to the cover and the cover gasket for air leaks. If no air leaks are apparent, inspect the diaphragm. A damaged diaphragm will not allow the fuel rack to open completely, acceleration will be sluggish and full engine power cannot be obtained.

Electrical System

Most of the electrical system testing can be performed on the engine. The wiring insulation must be in satisfactory condition, the wire and cable connections both clean and tight and the battery fully charged. It should be remembered an "on-engine" test usually indicates a component must be removed for further testing.

Battery

A load test should be made on a battery that discharges very rapidly when in use. To do this apply a resistance of two times the ampere/hour rating for a 6 volt battery, and three times the ampere/hour rating of a 12 volt battery across the battery main terminals. Allow the resistance to discharge the battery for 15 seconds and immediately test the battery voltage. A 6 volt battery in good condition will test 4.5 volts; a 12 volt battery in good condition will test 9 volts and a 24 volt battery will test 18 volts.

Starting System

Use a D.C. voltmeter to locate starting system components which do not function.

Turn the disconnect switch ON and push the circuit breaker reset button. Turn the HEAT-START switch to the START position. Starting motor solenoid operation is audible as the starter motor pinion engages with the ring gear on the engine flywheel. The solenoid operation should also close the electric circuit to the motor. Attach one voltmeter lead to the solenoid terminal that is connected to the motor. Ground the other lead. Turn the HEAT-START switch to START and observe the voltmeter. A battery voltage reading indicates the malfunction is in the motor. It must be removed for further testing. No voltmeter reading indicates that the solenoid contacts do not close and the solenoid must be repaired or the starter pinion clearance should be adjusted.

A starting motor solenoid that will not operate may not be receiving battery current. Attach one lead of the voltmeter to the solenoid battery cable connection. Ground the other lead. No voltmeter reading indicates a defective disconnect switch. A voltmeter reading indicates further testing is necessary.

Continue the test by attaching one voltmeter lead to the starting motor solenoid small wire terminal and the other lead to ground. Observe the voltmeter and turn the HEAT-START switch to START. A voltmeter reading indicates that the malfunction is in the solenoid. No voltmeter reading indicates that either the circuit breaker is defective or the HEAT-START switch does not close when turned to the START position.

Attach one lead of the voltmeter to the HEAT-START switch battery wire terminal and ground the other lead. A voltmeter reading indicates a defective switch. No voltmeter reading indicates the circuit breaker points are open. If the circuit breaker reset button will not close the points the circuit breaker is defective.

A starting motor that operates too slow can be overloaded by excessive mechanical friction within the engine being started. Slow starting motor operation can also be caused by shorts, loose connections and/or excessive dirt within the motor.

Glow plugs can be checked with an ammeter. Disconnect the wire lead from the glow plug terminal on the HEAT-START switch. Install an ammeter, in series, between the disconnected lead and the terminal on the switch. Observe the ammeter with the HEAT-START switch turned to the HEAT position. Each glow plug draws approximately 5 amperes. The ampere draw of one glow plug multiplied by the number of engine cylinders will be the total ampere draw of the glow plugs in the engine. A low reading is an indication of one or more defective glow plugs. Disconnect one glow plug lead at a time and observe the ammeter with the switch turned to HEAT. The disconnected glow plug that does not change the ammeter reading is the defective glow plug.

When no ammeter reading is obtained, test the HEAT-START switch. Attach one lead of the voltmeter to the glow plug wire terminal on the HEAT-START switch and the other lead to the ground. Observe the voltmeter and turn the switch to HEAT. No voltage indicates that the HEAT-START switch is defective.

Pinion Clearance Adjustment (Delco-Remy)

Whenever the solenoid is installed, the pinion clearance should be adjusted. The adjustment should be made with the starting motor removed.

Specific points related to the circuit connections for checking pinion clearance are: 1-Connector from MOTOR terminal on solenoid to motor. 2-SW terminal. 3-Ground terminal.

Bench test and adjust the pinion clearance at installation of solenoid as follows:

1. Install the solenoid without connector from the MOTOR terminal on solenoid to the motor.

2. Connect a battery, of the same voltage as the solenoid, to the terminal marked SW.

3. Connect the other side of battery to ground terminal or to solenoid frame.

4. MOMENTARILY flash a jumper wire from the solenoid terminal marked MOTOR to the frame or ground terminal. The pinion will shift into cranking position and will remain there until the battery is disconnected.

CIRCUIT FOR CHECKING AND ADJUSTING PINION CLEARANCE
2-SW terminal. 3-Ground terminal. 4-Ground flashing point.

5. Push pinion towards commutator end to eliminate free movement.

6. Pinion clearance should be .36 ± .03 in. (9,14 ± 0,76 mm).

7. Adjust clearance by removing plug and turning shaft nut.

PINION CLEARANCE CHECKING AND ADJUSTMENT LOCATION
5-Pinion. 6-Pinion clearance. 7-Shaft nut.

Charging System

The condition and state of charge of the battery at each regular inspection will indicate if the charging system is operating efficiently. An adjustment is necessary when the battery is always in a low state of charge or an excessive amount of water must be added to the battery (more than one ounce of water per cell per week or per every 50 service hours).

Alternator Regulators

When an alternator is either overcharging or undercharging the battery, the alternator charging rate can be adjusted. Remove the hollow head screw from the cover of the alternator regulator and use a screwdriver to turn the inside adjustment. Turn the adjustment one or two notches to increase or decrease the alternator charging rate.

5S9088 ALTERNATOR REGULATOR ADJUSTMENT SCREW LOCATION
1-Hollow head screw, located on opposite side of alternator from output terminal.

ALTERNATOR REGULATOR ADJUSTMENT SCREW LOCATION
(Remote mounted regulator)

Basic Block

Cylinder Liners

7M4321 Adapter Plate, 7M3977 Piston Ring Compressor, 7M3978 Piston Ring Expander, 8B7548 Push Puller (crossbar only), three 3H465 Plates (from 8B7548 Push Puller), four 3/4" NC Bolts 3 in. (76,2 mm) long, two 3/4" NC Bolts 7 in. (177,8 mm) long, eight 7M7875 head bolt washers, 8S2327 Base Post, 8S2329 Base, 7H1945 Holding Rod, 7H1948 Snug, 7H1942 Dial Indicator, 8S7116 Indicator Contact Point.

Check liner height projection as follows:

A. Make certain that the top plate and the cylinder liner flange are clean.

B. Use four 3/4" NC bolts 3 in. (76,2 mm) long, with two 7M7875 Washers (head bolt washers) on each bolt to secure the top plate to the cylinder block. Place two bolts with washers on each side of the cylinder liner. Tighten the bolts evenly to 50 lb. ft. (6,9 mkg).

SECURING TOP PLATE TO CYLINDER BLOCK

NOTE: To avoid moving bolts and washers as each liner is checked, install two bolts with washers on the side of each cylinder liner, along the entire length of the top plate. This requires fourteen bolts and twenty eight washers. Tighten all bolts evenly to 50 lb. ft. (6,9 mkg).

C. Invert a 3H465 Plate from an 8B7548 Push Puller, in the center of the 7M4321 Adapter Plate. Center the 8B7548 Crossbar in the inverted 3H465 Plate. Using two 3/4" NC bolts 7 in. (177,8 mm) long and two 3H465 Plates, secure the crossbar to the cylinder block as illustrated. Tighten the bolts evenly to 50 lb. ft. (6,9 mkg). Distance from bottom edge of crossbar, to top face of cylinder block top plate, must be the same on both sides of cylinder liner.

D. Using an 8S2327 Base Post, 8S2329 Base, 7H1945 Holding Rod, 7H1948 Snug, 7H1942 Dial Indicator and an 8S7116 Indicator Contact point, measure around each cylinder liner at four locations to get an accurate reading on height projection. Cylinder liner height projection must be .002-.006 in. (0,050-0,152 mm).

MEASURING LINER HEIGHT PROJECTION